Multilayer electronic component

ABSTRACT

A multilayer electric component includes a body including a dielectric layer and internal electrodes alternately stacked with the dielectric layer interposed therebetween and external electrodes disposed on the body and connected to the internal electrodes, wherein the internal electrodes include Cu and Ni and a coefficient of variation (CV) value of Cu/Ni (percent by weight) in a region thereof, 5 nm deep from an interface with the dielectric layer is 25.0% or less.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority to Korean PatentApplication No. 10-2020-0155482 filed on Nov. 19, 2020 in the KoreanIntellectual Property Office, the disclosure of which is incorporatedherein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to a multilayer electronic component.

BACKGROUND

A multilayer ceramic capacitor (MLCC), a multilayer electroniccomponent, is a chip-type condenser mounted on the printed circuitboards of various electronic products such as display devices includingliquid crystal displays (LCDs) and plasma display panels (PDPs),computers, smartphones, cell phones, and the like, to allow electricityto be charged therein and discharged therefrom.

The MLCC, advantageously compact, ensures high capacitance, facilitatesmounting, and thus may be used as a component of various types ofelectronic devices. Recently, as components of electronic devices havebeen miniaturized, demand for smaller multilayer ceramic capacitorshaving higher capacitance has increased.

However, as internal electrodes and dielectric layers have been reducedin thickness, internal electrode connectivity may be deteriorated and aninternal thickness deviation may increase, thereby reducing reliability.

However, as the internal electrode and the dielectric layer are thinned,high temperature load reliability, moisture resistance reliability, andthe like are deteriorated. Accordingly, there is a need for a methodcapable of excellently securing high temperature load reliability,moisture resistance reliability, etc. while internal electrodes anddielectric layers are thinned.

SUMMARY

An aspect of the present disclosure may provide a multilayer electroniccomponent including internal electrodes having improved reliability.

An aspect of the present disclosure may also provide a multilayerelectronic component in which high temperature load reliability ofinternal electrodes is improved.

An aspect of the present disclosure may also provide a multilayerelectronic component in which moisture resistance reliability ofinternal electrodes is improved.

Another aspect of the present disclosure may provide a compact,high-capacitance multilayer electronic component having highreliability.

According to an aspect of the present disclosure, a multilayer electriccomponent may include: a body including a dielectric layer and internalelectrodes alternately stacked with the dielectric layer interposedtherebetween; and external electrodes disposed on the body and connectedto the internal electrodes, wherein the internal electrodes include Cuand Ni and a coefficient of variation (CV) value of Cu/Ni (percent byweight) in a region of the internal electrode 5 nm deep from aninterface with the dielectric layer is 25.0% or less.

BRIEF DESCRIPTION OF DRAWINGS

The above and other aspects, features and other advantages of thepresent disclosure will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a schematic perspective view of a multilayer electroniccomponent according to an exemplary embodiment in the presentdisclosure;

FIG. 2 is a cross-sectional view taken along line I-I′ of FIG. 1 ;

FIG. 3 is a cross-sectional view taken along line II-II′ of FIG. 1 ;

FIG. 4 is an exploded perspective view schematically illustrating a bodyin which a dielectric layer and an internal electrode are stackedaccording to an exemplary embodiment in the present disclosure; and

FIG. 5 is an enlarged view of region K of FIG. 2 .

DETAILED DESCRIPTION

Exemplary embodiments of the present disclosure will now be described indetail with reference to the accompanying drawings. The shape and sizeof constituent elements in the drawings may be exaggerated or reducedfor clarity. In the drawings, for example, due to manufacturingtechniques and/or tolerances, modifications of the shape shown may beestimated. Thus, embodiments of the present disclosure should not beconstrued as being limited to the particular shapes of regions shownherein, for example, to include a change in shape results inmanufacturing. The following embodiments may also be constituted by oneor a combination thereof.

The present disclosure may, however, be exemplified in many differentforms and should not be construed as being limited to the specificembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the disclosure to those skilled in the art.

It will be apparent that though the terms first, second, third, etc. maybe used herein to describe various members, components, regions, layersand/or sections, these members, components, regions, layers and/orsections should not be limited by these terms. These terms are only usedto distinguish one member, component, region, layer or section fromanother region, layer or section. Thus, a first member, component,region, layer or section discussed below could be termed a secondmember, component, region, layer or section without departing from theteachings of the exemplary embodiments.

Spatially relative terms, such as “above,” “upper,” “below,” and “lower”and the like, may be used herein for ease of description to describe oneelement's relationship to another element(s) as shown in the figures. Itwill be understood that the spatially relative terms are intended toencompass different orientations of the device in use or operation inaddition to the orientation depicted in the figures. For example, if thedevice in the figures is turned over, elements described as “above,” or“upper” other elements would then be oriented “below,” or “lower” theother elements or features. Thus, the term “above” can encompass boththe above and below orientations depending on a particular direction ofthe figures. The device may be otherwise oriented (rotated 90 degrees orat other orientations) and the spatially relative descriptors usedherein may be interpreted accordingly.

The terminology used herein describes particular embodiments only, andthe present disclosure is not limited thereby. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. It willbe further understood that the terms “comprises,” and/or “comprising”when used in this specification, specify the presence of statedfeatures, integers, steps, operations, members, elements, and/or groupsthereof, but do not preclude the presence or addition of one or moreother features, integers, steps, operations, members, elements, and/orgroups thereof.

The contents of the present disclosure described below may have avariety of configurations and propose only a required configurationherein, but are not limited thereto.

In the drawings, an X direction may be defined as a second direction, anL direction, or a length direction, a Y direction may be defined as athird direction, a W direction, or a width direction, and a Z directionmay be defined as a first direction, a stacking direction, a Tdirection, or a thickness direction.

Multilayer Electronic Component

FIG. 1 is a schematic perspective view of a multilayer electroniccomponent according to an exemplary embodiment in the presentdisclosure.

FIG. 2 is a cross-sectional view taken along line I-I′ of FIG. 1 .

FIG. 3 is a cross-sectional view taken along line II-II′ of FIG. 1 .

FIG. 4 is an exploded perspective view schematically illustrating a bodyin which a dielectric layer and an internal electrode are stackedaccording to an exemplary embodiment in the present disclosure.

FIG. 5 is an enlarged view of region K of FIG. 2 .

Hereinafter, a multilayer electronic component according to an exemplaryembodiment in the present disclosure will be described in detail withreference to FIGS. 1 through 4 .

A multilayer electronic component 100 may include a body 110 includingdielectric layers 111 and internal electrodes 121 and 122 alternatelydisposed with the dielectric layers; and external electrodes 131 and 132disposed on the body 110 and connected to the internal electrodes 121and 122, wherein a coefficient of variation (CV) value of Cu/Ni (percentby weight) in a region of the internal electrode 5 nm deep from aninterface with the dielectric layer is 25.0% or less.

In the body 110, the dielectric layer 111 and the internal electrodes121 and 122 are alternately stacked.

There is no particular limitation to a specific shape of the body 110but, as shown, the body 110 may have a hexahedral shape or a shapesimilar thereto. Due to contraction (or shrinkage) of ceramic powderparticles included in the body 110 during a sintering process, the body110 may have a substantially hexahedral shape, but may not have ahexahedral shape with perfectly straight lines.

The body 110 may have first and second surfaces 1 and 2 opposing eachother in the thickness direction (Z direction), third and fourthsurfaces 3 and 4 connected to the first and second surfaces 1 and 2 andopposing each other in the width direction (Y direction), and fifth andsixth surfaces 5 and 6 connected to the first and second surfaces 1 and2, connected to the third and fourth surfaces 3 and 4, and opposing eachother in the length direction (X direction).

A plurality of dielectric layers 111 forming the body 110 are in asintered state, and adjacent dielectric layers 111 may be integratedsuch that boundaries therebetween may not be readily apparent withoutusing a scanning electron microscope (SEM).

According to an exemplary embodiment in the present disclosure, a rawmaterial for forming the dielectric layer 111 is not limited as long assufficient electrostatic capacitance may be obtained. For example, abarium titanate-based material, a lead composite perovskite-basedmaterial, or a strontium titanate-based material may be used. The bariumtitanate-based material may include a BaTiO₃-based ceramic powderparticles, and the ceramic powder particles may include BaTiO₃ and(Ba_(1-x)Ca_(x))TiO₃, Ba(Ti_(1-y)Ca_(y))O₃,(Ba_(1-x)Ca_(x))(Ti_(1-y)Zr_(y))O₃, or Ba(Ti_(1-y)Zr_(y))O₃ obtained bypartially dissolving calcium (Ca), zirconium (Zr), and the like inBaTiO₃.

As a material for forming the dielectric layer 111, various ceramicadditives, organic solvents, plasticizers, binders, dispersants, etc.may be added to the powder particles such as barium titanate (BaTiO₃)according to purposes of the present disclosure.

Meanwhile, a thickness td of the dielectric layer 111 may not belimited.

However, in general, if the dielectric layer is formed to be thin tohave a thickness less than 0.6 μm, in particular, if the thickness ofthe dielectric layer is 0.41 μm or less, moisture resistance reliabilitymay be degraded.

As described below, when Cu is evenly distributed in the interfacebetween the dielectric layer and the internal electrode according to anexemplary embodiment in the present disclosure, even when the dielectriclayer and the internal electrode are very thin, reliability may beimproved, and thus, sufficient reliability may be ensured even when thethickness of the dielectric layer is 0.41 μm or less.

Therefore, when the thickness of the dielectric layer 111 is 0.41 μm orless, the effect of improving reliability according to the presentdisclosure may be more remarkable.

The thickness td of the dielectric layer 111 may refer to an averagethickness of the dielectric layer 111 disposed between the first andsecond internal electrodes 121 and 122.

The average thickness of the dielectric layer 111 may be measured byscanning an image of a length-thickness (L-T) directional cross-sectionof the body 110 with a scanning electron microscope (SEM).

For example, regarding a certain dielectric layer extracted from animage of the length-thickness (L-T) cross-section taken at a centralportion of the body 110 in the width direction with the SEM, thicknessesthereof may be measured at 30 points at equal intervals in the lengthdirection, and an average value thereof may be calculated.

The thicknesses measured at 30 equally spaced points may be measured ata capacitance formation portion A referring to a region in which thefirst and second internal electrodes 121 and 122 overlap each other.

The body 110 may include the capacitance formation portion A formedinside the body 110 and forming capacitance with the first internalelectrode 121 and the second internal electrode 122 disposed to faceeach other with the dielectric layer 111 interposed therebetween andcover portions 112 and 113 formed above and below the capacitanceformation portion A.

In addition, the capacitance formation portion A is a part thatcontributes to formation of capacitance of the capacitor, which may beformed by repeatedly stacking a plurality of first and second internalelectrodes 121 and 122 with the dielectric layer 111 interposedtherebetween.

The upper cover portion 112 and the lower cover portion 113 may beformed by stacking a single dielectric layer or two or more dielectriclayers on upper and lower surfaces of the capacitance formation portionA in the thickness direction, respectively, and may serve to preventdamage to the internal electrodes due to physical or chemical stress.

The upper cover portion 112 and the lower cover portion 113 may notinclude an internal electrode and may include the same material as thatof the dielectric layer 111.

That is, the upper cover portion 112 and the lower cover portion 113 mayinclude a ceramic material, for example, a barium titanate(BaTiO₃)-based ceramic material.

Meanwhile, a thickness of the cover portions 112 and 113 may not belimited. However, a thickness tp of the cover portions 112 and 113 maybe 20 μm or less in order to more easily achieve miniaturization andhigh capacitance in the multilayer electronic component.

In addition, margin portions 114 and 115 may be disposed on sidesurfaces of the capacitance formation portion A.

The margin portions 114 and 115 may include a margin portion 114disposed on the sixth surface 6 of the body 110 and a margin portion 115disposed on the fifth surface 5 of the body 110. That is, the marginportions 114 and 115 may be disposed on both side surfaces of theceramic body 110 in the width direction.

As shown in FIG. 3 , the margin portions 114 and 115 may refer to aregion between both ends of the first and second internal electrodes 121and 122 and a boundary surface of the body 110 in a cross-section takenin the width-thickness (W-T) direction of the body 110.

The margin portions 114 and 115 may basically serve to prevent damage tothe internal electrodes due to physical or chemical stress.

The margin portions 114 and 115 may be formed as the internal electrodesare formed by applying a conductive paste on a ceramic green sheetexcluding a region where the margin portions are to be formed.

In addition, in order to suppress a step difference due to the internalelectrodes 121 and 122, the margin portions 114 and 115 may be formed bycutting the internal electrodes to be exposed to the fifth and sixthsurfaces 5 and 6 of the body after stacking and subsequently stacking asingle dielectric layer or two or more dielectric layers on both sidesurfaces of the capacitance formation portion A in the width direction.

The internal electrodes 121 and 122 are alternately stacked with thedielectric layer 111.

The internal electrodes 121 and 122 may include first and secondinternal electrodes 121 and 122. The first and second internalelectrodes 121 and 122 may be alternately disposed to face each otherwith a dielectric layer 111 configuring the body 110 interposedtherebetween and may be exposed to the third and fourth surfaces 3 and 4of the body 110, respectively.

Referring to FIG. 2 , the first internal electrode 121 may be spacedapart from the fourth surface 4 and exposed to the third surface 3, andthe second internal electrode 122 may be spaced apart from the thirdsurface 3 and exposed to the fourth surface 4.

In this case, the first and second internal electrodes 121 and 122 maybe electrically separated from each other by the dielectric layer 111disposed therebetween.

Referring to FIG. 4 , the body 110 may be formed by alternately stackinga ceramic green sheet on which the first internal electrode 121 isprinted and a ceramic green sheet on which the second internal electrode122 is printed and subsequently sintering the green sheets.

In the internal electrodes 121 and 122, a coefficient of variation (CV)value of Cu/Ni (percent by weight) in a region thereof 5 nm deep from aninterface with the dielectric layer may be 25.0% or less.

A work function of Ni is about 5.04 to 5.35, and a work function of Cuis about 4.53 to 5.10. Therefore, the work function tends to decrease asthe content of Cu increases in the Ni—Cu alloy.

If the Cu content is non-uniformly distributed at the interface betweenthe internal electrode and the dielectric layer, reliability may bedeteriorated as the work function is not uniform. This is because thework function at a location where the Cu content is relatively high islowered, thereby increasing the likelihood of current flow. Reliabilitymay be improved as Cu is evenly distributed in the internal electrode,and in particular, reliability may be improved when Cu is uniformlydistributed at the interface between the dielectric layer and theinternal electrode.

According to an exemplary embodiment in the present disclosure, bycontrolling the CV value of Cu/Ni (percentage by weight) in the regionof the internal electrode 5 nm deep from the interface with thedielectric layer 111 to 25.0% or less, the Cu content may be uniformlydistributed at the interface between the internal electrodes 121 and 122and the dielectric layer 111, thereby improving reliability.

If the CV value of Cu/Ni (percentage by weight) in the region of theinternal electrode 5 nm deep from the interface with the dielectriclayer 111 exceeds 25.0%, high temperature load reliability and moistureresistance reliability may become inferior.

Thus, the internal electrodes 121 and 122 preferably have the CV valueof 25.0% or less of Cu/Ni (percentage by weight) in the region 5 nm deepfrom the interface with the dielectric layer 111.

However, in order to further improve moisture resistance reliability, inthe internal electrodes 121 and 122, the CV value of Cu/Ni (percentageby weight) in the region 5 nm deeper from the interface with thedielectric layer may be 9.2% or less.

The CV value means that a standard deviation is expressed as apercentage over an average value.

In the internal electrodes 121 and 122, when the average value of Cu/Ni(percentage by weight) in the region thereof 5 nm deeper from theinterface with the dielectric layer is x1 and a standard deviation ofCu/Ni (percentage by weight) in the region thereof 5 nm deep from theinterface with the dielectric layer is S1, the CV value of Cu/Ni(percentage by weight) is s1/x1*100(%).

Referring to FIGS. 2 and 5 , regarding a length of the body 110 taken ata central portion of the body 110 in the width direction at the centerof the body in the width direction, a length of the body 110 in across-section in the thickness direction (L-T), and one internalelectrode positioned at the center of the body in the thicknessdirection, a quantitative analysis may be performed on ten points p1 top10 away by 5 nm from the upper and lower interface regions between theinternal electrodes and the dielectric layer toward the internalelectrode using energy dispersive X-ray spectrometer (EDS) to obtaineach value of Cu/Ni (percent by weight). Thereafter, an average x1 and astandard deviation s1 of each of the 10 Cu/Ni (percent by weight) valuesmay be obtained and a CV value of the Cu/Ni (percent by weight) may becalculated.

Meanwhile, the method of controlling the CV value of Cu/Ni (percentageby weight) may not be limited. For example, the CV value may becontrolled by adjusting a particle diameter, sintering conditions, andthe like of the conductive powder particles included in the conductivepaste for internal electrodes.

For a specific example, the CV value of Cu/Ni (percentage by weight) maybe controlled to 25.0% or less by controlling the average size of Cupowder particles included in the conductive paste for internalelectrodes to 120 nm or less.

In addition, the CV value of Cu/Ni (percentage by weight) may becontrolled to 9.2% or less by controlling the average size of Cu powderparticles included in the conductive paste for internal electrodes to 50nm or less.

Meanwhile, the content of Cu included in the internal electrode is notlimited, but may be preferably 0.4 to 6.0 wt %.

If the Cu content is less than 0.4 wt %, the effect of improvingreliability may be insufficient, and if the Cu content exceeds 6.0 wt %,reliability may be deteriorated even if Cu is uniformly distributed inthe internal electrode.

According to an exemplary embodiment in the present disclosure, Ni andCu included in the internal electrodes 121 and 122 may be included inthe form of a Ni—Cu alloy.

As Ni and Cu are included in the form of a Ni—Cu alloy, the effect of Cuaddition may be improved, and Cu included in the internal electrode maybe evenly distributed in the internal electrode.

Meanwhile, the thickness to of the internal electrodes 121 and 122 maynot be particularly limited.

However, in general, if the internal electrodes 121 and 122 are formedto be thin to have a thickness less than 0.6 μm, in particular, if thethickness of the internal electrodes 121 and 122 is 0.41 μm or less,moisture resistance reliability may be lowered.

As described above, when Cu is evenly distributed in the interfacebetween the dielectric layer and the internal electrode according to anexemplary embodiment in the present disclosure, even when the dielectriclayer and the internal electrode are very thin, reliability may beeffectively improved, and thus, sufficient moisture resistancereliability may be ensured even when the thickness of the internalelectrodes 121 and 122 is 0.41 μm or less.

Therefore, when the thickness of the internal electrodes 121 and 122 is0.41 μm or less, the effect of improving reliability according to thepresent disclosure may be more remarkable and miniaturization and highcapacitance of the capacitor component may be more easily achieved.

The thickness to of the internal electrodes 121 and 122 may refer to anaverage thickness of the internal electrodes 121 and 122.

The average thickness of the internal electrodes 121 and 122 may bemeasured by scanning an image of a length and thickness directional(L-T) cross-section of the body 110 with an SEM.

For example, in an image obtained by scanning a cross-section of thebody 110 in the length and thickness directions (L-T) taken at a centralportion of the body 110 in the width direction (W), certain first andsecond internal electrodes 121 and 122 may be extracted, and thicknessesthereof at 30 points at equal intervals in the length direction may bemeasured, and an average value of the measured thicknesses may becalculated.

The external electrodes 131 and 132 may be disposed on the body 110 andconnected to the internal electrodes 121 and 122.

As shown in FIG. 2 , the external electrodes 131 and 132 may be disposedon the third and fourth surfaces 3 and 4 of the body 110 and connectedto the first and second internal electrodes 121 and 122, respectively.

In this exemplary embodiment, a structure in which the multilayerelectronic component 100 has two external electrodes 131 and 132 isdescribed, but the number or shape of the external electrodes 131 and132 may be modified according to shapes of the internal electrodes 121and 122 or other purposes.

Meanwhile, the external electrodes 131 and 132 may be formed of anymaterial as long as the material has electrical conductivity such as ametal, and a specific material may be determined in consideration ofelectrical characteristics and structural stability, and further, theexternal electrodes 131 and 132 may have a multilayer structure.

For example, the external electrodes 131 and 132 may include electrodelayers 131 a and 132 a disposed on the body 110 and plating layers 131 band 132 b formed on the electrode layers 131 a and 132 a.

For a more specific example of the electrode layers 131 a and 132 a, theelectrode layers 131 a and 132 a may be sintered electrodes including aconductive metal and glass or resin-based electrodes including aconductive metal and a resin.

In addition, the electrode layers 131 a and 132 a may have a form inwhich a sintering electrode and a resin-based electrode are sequentiallyformed on the body. In addition, the electrode layers 131 a and 132 amay be formed by transferring a sheet including a conductive metal ontothe body or by transferring a sheet including a conductive metal ontothe sintering electrode.

A material having excellent electrical conductivity may be used as theconductive metal included in the electrode layers 131 a and 132 a, andthe material is not particularly limited. For example, the conductivemetal may be one or more of nickel (Ni), copper (Cu), and alloysthereof.

The plating layers 131 b and 132 b serve to improve mountingcharacteristics. The plating layers 131 b and 132 b are not limited intype and may be plating layers including at least one of Ni, Sn, Pd, andalloys thereof or may be formed of a plurality of layers.

For a more specific example of the plating layers 131 b and 132 b, theplating layers 131 b and 132 b may include a Ni plating layer or an Snplating layer, and in this case, the Ni plating layer and the Sn platinglayer may be sequentially formed on the electrode layers 131 a and 132 aor the Sn plating layer, the Ni plating layer, and the Sn plating layermay be sequentially formed on the electrode layers 131 a and 132 a. Inaddition, the plating layers 131 b and 132 b may include a plurality ofNi plating layers and/or a plurality of Sn plating layers. Further, theplating layers 131 b and 132 b may have a form in which a Ni platinglayer and a Pd plating layer are sequentially formed on the electrodelayers 131 a and 132 a.

A size of the multilayer electronic component 100 may not beparticularly limited.

However, in order to achieve both miniaturization and high capacitance,the number of layers needs to be increased by reducing the thickness ofthe dielectric layer and the internal electrode, and thus, the effect ofimproving reliability according to the present exemplary embodiment maybe remarkable in a multilayer electronic component having a 0402 size(length×width, 0.4 mm×0.2 mm) or less.

Accordingly, when the length of the multilayer electronic component is0.44 mm or less and the width thereof is 0.22 mm or less, taking intoaccount a manufacturing error and the size of external electrode, thereliability improvement effect according to the present disclosure maybe more remarkable.

Hereinafter, a method of manufacturing a multilayer electronic component100 according to an exemplary embodiment in the present disclosure willbe described.

First, a plurality of ceramic green sheets are prepared.

The ceramic green sheet is for forming the dielectric layer 111 of thebody 110, and a slurry may be prepared by mixing ceramic powderparticles, a polymer, and a solvent, and the slurry may be formed in asheet shape having a predetermined thickness through a method such as adoctor blade or the like.

Thereafter, a conductive paste for internal electrodes is printed with apredetermined thickness on at least one surface of each ceramic greensheet to form an internal electrode.

The conductive paste for internal electrodes includes Ni powderparticles and Cu powder particles.

In this case, an average size of the Cu powder particles may be 120 nmor less. By controlling the average size of the Cu powder particles tobe 120 nm or less, the CV value of Cu/Ni (percent by weight) in theregion of the internal electrode 5 nm deep from the interface with thedielectric layer may be controlled to 25.0% or less.

In addition, the average size of the Cu powder particles may be 50 nm orless. By controlling the average size of the Cu powder particles to 50nm or less, the CV value of Cu/Ni (percentage by weight) in the regionof the internal electrode 5 nm deep from the interface with thedielectric layer may be controlled to 9.2% or less.

As a printing method of the conductive paste for internal electrodes, ascreen printing method or a gravure printing method may be used.

Referring to FIG. 4 , the ceramic green sheet on which the firstinternal electrode 121 is printed and the ceramic green sheet on whichthe second internal electrode 122 is printed are alternately stacked andpressed in a stacking direction to compress the plurality of stackedceramic green sheets and the internal electrodes formed on the ceramicgreen sheets to form a stack.

In addition, at least one ceramic green sheet may be stacked above andbelow the stack to form cover portions 112 and 113.

The cover portions 112 and 113 may have the same composition as thedielectric layer 111 located inside the stack and differ from thedielectric layer 111 in that the cover portions 112 and 113 do notinclude internal electrodes.

Thereafter, each region of the stack corresponding to one capacitor iscut into a chip, and the chip is fired at high temperatures to completethe body 110.

Thereafter, exposed portions of the first and second internal electrodesexposed to both sides of the body 110 may be covered to form first andsecond external electrodes 131 and 132 such that the first and secondexternal electrodes 131 and 132 are electrically connected to the firstand second internal electrodes.

At this time, surfaces of the first and second external electrodes 131and 132 may be plated with nickel or tin, if necessary.

EXAMPLE

A sample chip in which internal electrodes were formed using aconductive paste for internal electrodes in which 6.0 wt % of Cu powderparticles having the average size of Table 1 was added based on 100 wt %of Ni powder particles was prepared.

A CV value of Cu/Ni (percentage by weight) in a region of the internalelectrode 5 nm deep from an interface with a dielectric layer wasmeasured, and high temperature load reliability and moisture resistancereliability were evaluated.

As for the CV value, regarding a length of the body 110 taken at acentral portion of the body 110 in the width direction at the center ofthe body in the width direction, a length of the body 110 in across-section in the thickness direction (L-T), and one internalelectrode positioned at the center of the body in the thicknessdirection, a quantitative analysis may be performed on ten points p1 top10 away by 5 nm from the upper and lower interface regions between theinternal electrodes and the dielectric layer toward the internalelectrode using energy dispersive X-ray spectrometer (EDS) to obtaineach value of Cu/Ni (percent by weight), and an average x1 and astandard deviation s1 of each of the 10 Cu/Ni (percent by weight) valuesmay be obtained and the CV value (=s1/x1*100(%)) of the Cu/Ni (percentby weight) may be calculated.

As for high-temperature load reliability, high-temperature load test wascarried out on 400 samples per test No. under the conditions of 125° C.and 8 V, and MTTF was measured. In this case, a time during which theinsulation resistance was 10 kΩ or less was determined as a failuretime.

As for moisture resistance reliability, 8V was applied to 400 samplesper Test No. at a temperature of 85° C. and with relative humidity of85% for 60 hours, samples whose insulation resistance value was loweredto below 1/10 relative to initial values were evaluated as failures, andthe percentage of the number of defective samples was described.

TABLE 1 Average size Moisture of Cu powder resistance particle CV valueMTTF failure Test No. (nm) (%) (hr) (%) 1  20 4.1 59.5 0.7 2  30 6.355.1 1.3 3  50 9.2 57.8 1.5 4  70 13.5 56.6 5.0 5  90 18.8 53.3 5.5 6 120 25.0 50.3 7.5 7* 130 26.1 45.5 9.9 8* 150 28.5 40.2 18.5 9* 180 29.038.4 24.8

It can be seen that, Test Nos. 7 to 9 in which the CV value is more than25.0%, have short MTTF and a high moisture resistance defect rate.

Meanwhile, it can be seen that, Test Nos. 1 to 6 in which the CV valueis 25.0% or less have high temperature reliability and excellentmoisture resistance reliability.

In addition, it can be seen that, Test Nos. 1 to 3 in which the CV valueis 9.2% or less have very low moisture resistance failure, thus havingexcellent moisture resistance reliability.

As set forth above, according to exemplary embodiments of the presentdisclosure, reliability of the multilayer electronic component may beimproved.

While exemplary embodiments have been shown and described above, it willbe apparent to those skilled in the art that modifications andvariations could be made without departing from the scope of the presentdisclosure as defined by the appended claims.

What is claimed is:
 1. A multilayer electric component comprising: abody including a dielectric layer and internal electrodes alternatelystacked with the dielectric layer interposed therebetween; and externalelectrodes disposed on the body and connected to the internalelectrodes, wherein the internal electrodes include Cu and Ni and acoefficient of variation (CV) value of Cu/Ni (percent by weight) in aregion thereof, 5 nm deep from an interface with the dielectric layer is25.0% or less.
 2. The multilayer electric component of claim 1, whereinthe internal electrodes comprise a sintered conductive material, theconductive material including Cu powder particles having an average sizeof 120 nm or less.
 3. The multilayer electric component of claim 1,wherein the CV value is 9.2% or less.
 4. The multilayer electriccomponent of claim 2, wherein the average size of the Cu powderparticles is 50 nm or less.
 5. The multilayer electric component ofclaim 1, wherein content of Cu in the internal electrodes is in a rangefrom 0.4 wt % to 0.6 wt %.
 6. The multilayer electric component of claim1, wherein the internal electrodes comprise an Ni—Cu alloy.
 7. Themultilayer electric component of claim 1, wherein an average thicknessof the internal electrodes is 0.41 μm or less.
 8. The multilayerelectric component of claim 1, wherein an average thickness of thedielectric layer is 0.41 μm or less.
 9. The multilayer electroniccomponent of claim 1, wherein the multilayer electronic component has alength of 0.44 mm or less and a width of 0.22 mm or less.
 10. Amultilayer ceramic capacitor comprising: internal electrodes alternatelystacked with dielectric layers interposed therebetween, the internalelectrodes comprising a sintered conductive material including Cu andNi, a coefficient of variation (CV) of a ratio of Cu to Ni (percent byweight) measured at a depth of 5 nm from an interface between one of theinternal electrodes and an adjacent dielectric layer is 25.0% or less.11. The multilayer electronic component of claim 10, wherein the CVvalue is (s1/x1)×100, wherein s1 is standard deviation of the ratio ofCu to Ni and x1 is average value of the ratio of Cu to Ni.
 12. Themultilayer electronic component of claim 10, wherein content of Cu inthe internal electrodes is in a range from 0.4 wt % to 6.0 wt %.
 13. Themultilayer electronic component of claim 10, wherein the conductivematerial including Cu powder particles having an average size of 120 nmor less.
 14. A multilayer ceramic capacitor comprising internalelectrodes comprising a sintered conductive material, the conductivematerial including Ni and Cu powder particles having an average size of120 nm or less, wherein content of Cu in the internal electrodes is in arange from 0.4 wt % to 6.0 wt %, wherein a coefficient of variation (CV)of a ratio of Cu to Ni (percent by weight) measured at a depth of 5 nmfrom an interface between one of the internal electrodes and an adjacentdielectric layer is 25.0% or less, wherein the CV value is (s1/x1)×100,wherein s1 is standard deviation of the ratio of Cu to Ni and x1 isaverage value of the ratio of Cu to Ni.